Abstract:
Increasing incidences of drought-induced tree mortality are being recorded worldwide,
including Africa. African forests cover a significant proportion of the continent, which
implies that African forest sustainability is threatened from a climate change perspective.
This is especially problematic in a developing nation context, since forest ecosystems such as
plantation forestry provide important goods and services that sustain human well-being and
economic growth. Disentangling the likely triggers of tree mortality (including those linked
to drought) in landscapes would not only explain the mechanisms underlying local die-offs,
but also better predict future mortality events. Methods applied in the field of ecophysiology
are particularly useful to study in situ plant responses to an environment. We consider the
status quo of global peer-reviewed publication outputs during the past century that have made
use of key ecophysiological research approaches, specifically studies concerning ‘tree xylem
anatomy’, ‘tree xylem cavitation’, ‘tree leaf gas-exchange’, ‘tree xylem hydraulic
conductivity’. We highlight the growth and applicability of this research field in
understanding tree ecology. We also assess the role that the forestry sector has had in
promoting such research to ensure future-proof forest products. Most importantly we consider
how Africa with its vast forested landscapes fits within this research spectrum. The last
decade saw an increase of up to 60% in the total number of articles published, particularly
with a focus on tree xylem cavitation and conductivity. While forest research contributed
greatly to the global tally of ecophysiological studies, and such studies in Africa have also
increased by up to 88% the past decade, there remains a general lack of this research topic in
the continent. It is clear an optimisation of applied ecophysiological concepts and techniques
will promote an improved understanding of tree mortality patterns. And we argue that ecophysiological data will be crucial to future-proof tree improvement strategies in African
commodity production landscapes, especially given future drier climates.
